Copy Number Variations

Researchers Reveal 18 Novel Subtype-Dependent Genetic Variants for Autism Spectrum Disorders and Identify Potential Genetic Markers for Diagnostic Screening

Source: 
Science Daily
Date Published: 
April 28, 2011
Abstract: 

By dividing individuals with autism spectrum disorders (ASD) into four subtypes according to similarity of symptoms and reanalyzing existing genome-wide genetic data on these individuals vs. controls, researchers at the George Washington University School of Medicine and Health Sciences have identified 18 novel and highly significant genetic markers for ASD. In addition, ten of the variants were associated with more than one ASD subtype, providing partial replication of these genetic markers. This study thus identifies candidate genes for ASD and potential subtype-dependent genetic markers for diagnostic screening.

Autism Spectrum Disorder Linked to Genetic Synaptic Behaviors

Source: 
Medical News Today
Date Published: 
April 21, 2011
Abstract: 

It seems that the place where your brain transfers electricity between synapses and how your genes determine how these processes function, are tied to autism in one way or another. There can be genetically driven disturbances in this process that lead to varying levels of autism according to a new study of DNA from approximately 1,000 autistic children and their kin.

Gene Variants in Autism Linked to Brain Development

Source: 
Science Daily
Date Published: 
March 7, 2011
Abstract: 

New research on the genomics of autism confirms that the genetic roots of the disorder are highly complicated, but that common biological themes underlie this complexity. In the current study, researchers have implicated several new candidate genes and genomic variants as contributors to autism, and conclude that many more remain to be discovered. While the gene alterations are individually very rare, they mostly appear to disrupt genes that play important functional roles in brain development and nerve signaling.

Gene Variants in Autism Linked to Brain Development

Source: 
Journal of Molecular Psychiatry, Gai et al.
Date Published: 
March 2011
Year Published: 
2011

This research on the genomics of autism confirms that the genetic roots of the disorder are highly complicated, but that common biological themes underlie this complexity. In the current study, researchers have implicated several new candidate genes and genomic variants as contributors to autism, and conclude that many more remain to be discovered. While the gene alterations are individually very rare, they mostly appear to disrupt genes that play important functional roles in brain development and nerve signaling. While an association between genomic variants in certain nervous system processes and autism has been hypothesized in the past, this research definitively links these biological functions to autism. 

"This large study is the first to demonstrate a statistically significant connection between genomic variants in autism and both synaptic function and neurotransmission," said senior author Peter S. White, Ph.D., a molecular geneticist and director of the Center for Biomedical Informatics at The Children's Hospital of Philadelphia. Synapses are the contact points at which nerve cells communicate with other nerve cells, while neurotransmitters are the chemical messengers carrying those signals.

"Prior genomic studies of autism have successfully identified several genes that appear to confer risk for autism, but each gene appears to contribute to only a small percentage of cases," said the lead author, Xiaowu Gai, Ph.D. "Our approach considered whether groups of genes with common biological functions collectively accounted for a greater percentage of autism risk."

-- via Science Daily http://www.sciencedaily.com/releases/2011/03/110301111243.htm.

Researchers Develop Mouse Model To Help Find How A Gene Mutation Leads To Autism

Source: 
Medical News Today
Date Published: 
December 20, 2010
Abstract: 

Researchers from Mount Sinai School of Medicine have found that when one copy of the SHANK3 gene in mice is missing, nerve cells do not effectively communicate and do not show cellular properties associated with normal learning. This discovery may explain how mutations affecting SHANK3 may lead to autism spectrum disorders (ASDs). The research is currently published in Molecular Autism.

Inhibitory Neurons Key to Understanding Neuropsychiatric Disorders

Source: 
Science Daily
Date Published: 
November 11, 2010
Abstract: 

In 1999, Baylor College of Medicine researcher Dr. Huda Zoghbi and her colleagues identified mutations in the gene called MECP2 as the culprit in a devastating neurological disorder called Rett syndrome . In new research in mice published in the current issue of the journal Nature, Zoghbi and her colleagues demonstrate that the loss of the protein MeCP2 in a special group of inhibitory nerve cells in the brain reproduces nearly all Rett syndrome features.

New Autism Susceptibilty Genes Identified

Source: 
Medical News Today
Date Published: 
June 10, 2010
Abstract: 

Mount Sinai researchers and the Autism Genome Project Consortium (AGP) announced that they have identified new autism susceptibility genes that may lead to the development of new treatment approaches. These genes, which include SHANK2, SYNGAP1, DLGAP2 and the X-linked DDX53-PTCHD1 locus, primarily belong to synapse-related pathways, while others are involved in cellular proliferation, projection and motility, and intracellular signaling

New Genetic Risk Factor for Both Autism and Schizophrenia

Source: 
Science Daily
Date Published: 
November 4, 2010
Abstract: 

Researchers have uncovered a prominent genetic risk factor for autism spectrum disorders and schizophrenia is a small genomic deletion. Remarkably, they found the same deletion on chromosome 17 in 24 separate patients. This CNV was absent in 52,448 controls, making the finding statistically significant. Someone with this deletion is 13.58 times more likely to develop ASD or schizophrenia than is someone lacking this CNV. This gene mutation is also known to cause kidney disease (renal cysts and diabetes syndrome, RCAD).

Developmental Problems, Some Exist in the Genes

Source: 
Medical News Today
Date Published: 
August 18, 2010
Abstract: 

DNA for each individual contains variants that are more or less common in the overall population.

Some gene variations are actually genetic deletions, where sections of DNA 'code' are missing entirely. These variants are likely to have important effects on gene function and, therefore, likely to contribute to diseases associated with that gene. But what happens when multiple genes are disrupted in a single family?

Disturbances in Certain Genes Play a Role in Autism

Source: 
Medical News Today
Date Published: 
August 17, 2010
Abstract: 

Together with colleagues from an international research group, autism researcher Christopher Gillberg of the University of Gothenburg, Sweden, has found in a new study that autism can be partially explained by abnormalities in certain genes. The group's results could, in the long run, pave the way for more appropriate treatments for autism.

In the article the group reveals that a survey of 1,000 individuals with autism and 1,300 without showed that Copy Number Variants (CNVs) sub-microscopic abnormalities in the chromosomes are heavily over-represented in autistic people.